Association of Helicobacter pylori with coronary artery disease and myocardial infarction assessed by myocardial perfusion imaging.

KeY wOrds: c hronic inflammation plays a pivotal role in the initiation, progression and complications of coronary atherosclerosis together with major risk factors for coronary artery disease [1]. A number of seroepidemiologic studies have suggested an association between coronary atherosclerosis and chronic infections [2]. Helicobacter pylori infection is the most common chronic bacterial infection worldwide [3]. The infection colonizes gastric mucosa and can elicit life-long inflammatory and immune responses concurrently with the release of various bacterial and host-dependent cytotoxic substances [4]. Several studies have found an association of H. pylori infection with the development of CAD1 [4-6]; others dispute this finding [7,8]. Today, this issue is still controversial. Another disagreement among researchers is whether an infection with virulent cytotoxic strains of H. pylori bearing the cytotoxin-associated gene A (CagA-positive strains) is associated with CAD [9,10]. A myocardial perfusion imaging stress test is widely regarded as a clinically useful non-invasive imaging modality for diagnosing patients with suspected CAD [11]. Although coronary angiography is a valuable diagnostic test for detecting coronary artery stenosis, it does not provide perfusion or contractility data when the heart is physiologically stressed. Non-invasive stress MPI2 can detect myocardial ischemia, as reflected by reversible perfusion defects, important components in diagnosing atherosclerotic obstructive CAD [11], and a strong predictor of adverse outcomes such as future myocardial infarctions. MI3 on an MPI study is diagnosed as a non-reversible fixed defect with no significant changes in activity between post-stress and rest images [12]. MPI is an established method for non-invasively assessing the functional significance of coronary stenosis and can reveal valuable information of risk stratification. Patients with stable angina and normal MPI results have a low mortality risk and, therefore, no intervention is required [13]. CAD = coronary artery disease MPI = myocardial perfusion imaging MI = myocardial infarction